Automobile heater



July 21. 942 H. J. DE N. MccoLLuM 2,290,151

AUTOMOBILE HEATER original Filed Jan. s, 195s is in operation.

Patented July 21, 1942 2,290,151 l AUTOMOBILE HEATER. l

' Henry J. De N. McCollum, Chicago, Ill.

Original application January 6, 1938, Serial No. 183,598. Divided andthis application July 31,

1939, Serial No. 287,553

Claims.

My invention relates generally to automobile heaters, and moreparticularly to heaters of the internal combustion type. The presentinvention is an improvement on the heater shown in my priorapplications, Serial No. 61,213, led Janu- '5 ary 28, 1936, and SerialNos. 120,523 and 120,524, filed January14, 1937, and is a division of mycopending application Serial No. 183,598, filed January 6, 1938.`

In using an automobile heater of the internal combustion type upon anautomobile, the gases of combustion from the heater are drawn into theintake manifold of the automobile engine. Compensation for thisadditional supply of gases to the intake manifold may easily be made l5by regulating the engine carburetor so as slightly to increase theidling speed of the engine. Of course this difficulty is encounteredrelatively infrequently, and only when the eauburetor is very delicatelyadjusted to the needs of the engine.

In accordance with my invention, I provide means, controlled incidentalto the operation of the heater, for securing more uniform idling andnormal operation of the engine irrespective of whether or not the heateris in operation. Such' means may assume manydiierent forms, but isdisclosed herein as controlled by the degree of intake manifold vacuum.

It is thus an object of my invention to provide an improved form ofautomobile heater having means for securing uniform operation of theengine irrespective of whether or not the heater is operating.

Itis a further object of my invention to provide automatic means, underthe control of the intake manifold vacuum, for admitting a restricted.amount of air to the intake manifold of the, engine during the periodsin` which the heater l Other objects will appear from the followingdescription, reference being had to the accompanying drawing, in which:

Fig. 1 is a fragmentary centrallongitudinal sectional view of a heatershown installed upon v an automobile and including an intake manifoldvacuum responsive valve for admitting air to the intake manifold of theengine; and

Fig. 2 is a central vertical sectional view .of the air-admitting valve.

The heater comprises generally a combustion chamber I0 formed in acasting I2 which is secured to a back plate I4. The latter is connectedb'y brackets I6 tothe dash I8 of the vehicle. A radiator 20 is securedto the combustion cham- 55 ber casting I2 and is surrounded by a shell22 over which heat radiating fins 24 are secured. Within the radiator 20is a circuitous passageway which terminates adjacent a nozzle 25 whichforms means for compensating for changes in the in my aforesaidapplications.

degree of vacuum in the intake manifold. This nozzle communicates with apassageway 26 in the casting I2 to which a fitting 28 is connected, thelatter being connected by a conduit 30 with the intake manifold 32 ofthe engine. A valve 34 is engageable with the mouth of vthe nozzle 25and is operable by means of a control button 36. Liquid fuel issuppliedto the heater from a reservoir 38, which may be either thefloatbowl of the engine carburetor or a separate auxiliary reservoir forliquid fuel. The fuel is drawn from the reservoir 38 through a conduit40 to a carbureting device 42 where the fuel is mixed with the properamount of air to form a combustible mixture which is fed to thecombustion chamber.

At the side of the combustion chamber I0 is located an igniter chamberwhich communicates with the combustion chamber through a large port 48.The igniter is preferably a coil of high resistance wire which may beelectrically heated to incandescence and thereby ignite the mixture ofliquid fuel and air passing through the combustion chamber. Thecombustion chamber is partially closed by a slightly porous refractoryvreigniter plug 52 which has passageways eX- ucts of combustion.

The air from the passenger compartment of the vehicle is circulated pastthe heat radiating fins 24 by means of a fan 54 driven by a motor 56. Asuitable switch mechanism 58 is mounted adjacent the end of the radiator20 and arranged to be controlled by the button `36 and by a strip ofthermostatic bimetal 60 which is in heat conducting relationship withthe radiator. This switch mechanism and its vmethod of operation is morefully disclosed and claimed in my aforesaid application, Serial No.120,524. It will sufce here to say that the switch is operable when thecontrol button is,` pulled outwardly to open the valve 34, to close acircuit'connecting the igniter with a source of current, and is operatedthereafter by the thermostatic bimetal strip 60 to open the ignitercircuit and to close a circuit connecting the fan motor 56' with thesource of current. When the control button 36 is pushedl inwardly, thevalve 34 is closed and the circuits supplying both the fan motor and theigniter ar opened. As thus far described, the heater is disclosed of thepresent invention relates particularly to threaded into the intakemanifold 32. The upper end. ofthe housing is closed by alexiblediaphragm 82, the edges of -the diaphragm being` clamped to the rim ofthe housing 80 by means The improvement* of a cap 83 having aperturesv84 therein. 'I'he diaphragm 82 has a valve seat member 86 riveted orotherwise secured thereto at its center. The diaphragm is normally heldin its upper position, as shown in Fig. 2, by a conical compression coilspring 88. A valve stem 92 having a reduced diameter portion 90 isthreaded in the cap 83, being locked in adjusted position by a nut 93. Avalve 95 cooperable with the valve seat 86 is secured at'the lower endof the reduced diameter portion 90 of the stem. The annular passageway94 between the reduced diameter portion 90 of the stem and the valveseat 86 is of relatively small cross sectional area, in the order of.003 of a square inch. The spring 88 is of such strength that thediaphragm will be drawn downwardly to bring the valve seat 86 againstthe valve 95 only when the intake manifold vacuum is relatively great,as when the engine is idling. During other periods, a restricted amountof air will ow through the passageway 94 and intake manifold 32, andthereby improve the operation of the engine.

When the heater is in operation, the .intake manifold vacuum is slightlyreduced, so that the diaphragm will be forced upwardly by the spring 88,and thereby raise the valve seat 86 from contact with the valve 95, thusproviding an additional supply of air for the automobile engine, whichis` eective to improve the performance of the engine at idling speeds.

In operation the valve 86--95 admits a predetermined proportion of airfrom the atmosphere to the intake manifold whenever the heater is inoperation, and thereby improves the performance of the engine byassuring a more uniform supply ol fue] and air mixture thereto. Theadmission of the auxiliary supply of air to the` intake manifold takesplace automatically whenever the heater is in operation, since theadmission of gases to the intake manifold from the heater tends toreduce the intake manifold vacuum. While air is admitted to the intakemanifold whenever the vacuum is low, the effect upon the mixture isslight except at idling speeds, because the port 94 is of relativelysmall cross-sectional area, and admits a relatively small quantity ofair when the throttle is open.

The valve housing 80 is preferably connected to the intake manifold at apoint close to the connection of the conduit 3U thereto, so that it willrespond rapidly to changes in vacuum' caused by the flow of gases fromthe latter conduit.

While I have shown and described a preferred embodiment of my invention,it will be readily understood by those skilled in the art thatvariations may be made in the construction disclosed without departingfrom the basic features of my invention. I therefore do not wish to belimited to the precise construction disclosed, but wish to includewithin the scope of my invention all such modifications and variationswhich will readily suggest themselves to those skilled in the art.

closing the opening in said diaphragm when the latter is moved inwardlyunder the influence of a reduction of pressure in the intake manifold,sa diaphragm being adapted to move away from -said valve and permit theflow of atmospheric air through the aperture therein Whenever the degreeof pressure in the intake manifold exceeds a predetermined maximumvalue.

2. In a device of the class described, the combination of a cup-likeelement having a part connecting the interior of the cup with the intakemanifold of an automobile engine, a centrally apertured flexiblediaphragm, an apertured cover securing the peripheral edge of saiddiaphragm of the rim of said element, a stem adjustably secured to saidcover and projecting freely through the aperture in said diaphragm, avalve secured to the inner end of said stem and arranged to close theaperture in said diaphragm when the central portion of the latter isflexed inwardly, and a spring normally holding said diaphragm away fromsaid valve.

3. In a system in which an internal combustion type of heater isconnected to have the products of combustion of the heater drawn intothe intake manifold of the engine, means for compensating for thedilution of the charge in the intake manifold by such products ofcombustion comprising, a hollow element connected to the intakemanifold, an apertured flexible diaphragm forming one wall of saidelement, an apertured cap secured over said diaphragm, a stem adjustablysecured to said cap and having a portion of reduced diameter projectingthrough the aperture in said diaphragm, a valve of larger diameter thanthe aperture in said diaphragm and secured t0 the inner end of thereduced diameter portion' of said stem, said valve being operable toclose the aperture in said diaphragm when the latter is flexed inwardlywith respect to said element due to a reduction of the pressure therein,and a spring opposing such inward movement of said diaphragm.

4. In a device of the class described, the combination of a cupconnected to the intake manifold of an automobile engine, an aperturedflexible diaphragm secured to the rim of said cup, an apertured coverover said diaphragm, a stem adjustably secured to said cover andprojecting freely through the aperture in said diaphragm, a valve seatmember secured to said diaphragm around the aperture therein, a valve onthe inner end of said stem and arranged to engage said valve seat memberwhen the central portion of the latter is exed inwardly, and resilientmeans holding said seat member away from said valve. 5. In aninstallation comprising an internal combustion engine having a manifoldfor supplying a combustible mixture to said engine, a combustion heaterdischarging into said manifold. means for operating said heater at willduring the operation of said engine, said installation beingcharacterized by the provision of a valve for bleeding air into saidmanifold only when said engine and heater are operating, said valvecomprising a diaphragm having an opening therethrough, a stationaryvalve member for closing said opening when said diaphragm is in oneposition, a spring for urging said diaphragm away from said oneposition, and conduit means connecting said manifold and diaphragm sothat operation of said heater results in movement of said diaphragm awayfrom said valve member.

HENRY J DE N. MCCOLLUM.

